Nonclassicality criteria: Quasiprobability distributions and correlation functions
نویسنده
چکیده
We use the exact calculation of the quantum mechanical, temporal characteristic function χ (η) and the degree of second-order coherence g(2)(τ ) for a single-mode, degenerate parametric amplifier for a system in the Gaussian state, viz., a displaced-squeezed thermal state, to study the different criteria for nonclassicality. In particular, we contrast criteria that involve only one-time functions of the dynamical system, for instance, the quasiprobability distribution P (β) of the Glauber-Sudarshan coherent or P representation of the density of state and the Mandel QM (τ ) parameter, versus the criteria associated with the two-time correlation function g(2)(τ ).
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